Perhaps you should try some spelling variations:
"series estudios peruanoss." » "series estudios peruanos.", "serie estudios peruanoss.", "seis estudios peruanoss.", "tres estudios peruanoss."
"dos estudios urbanos." » "dos estudio urbanos.", "dos estudios peruanoss.", "dos estudios hispanos."
"los estudios urbano." » "los estudio urbano.", "los estudios peruanos.", "los estudios hispano."

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: (((("series estudios peruanoss.") OR ("dos estudios urbanos."))) OR ("los estudios urbano."))~.
• Removing quotes may allow a broader search: (((( series estudios peruanoss. ) or ( dos estudios urbanos. ))) or ( los estudios urbano. ))~.
• Adding a wildcard symbol may retrieve word variants: (((("series estudios peruanoss.") or ("dos estudios urbanos."))) or ("los estudios urbano."))*.